Any way to reference an attribute of a parameter in the query? - jpa

Is there any way to reference an attribute of a parameter that is part of a query for a JPA repository?
My sample is
#Entity
public class Matchday implements Serializable {
#Id
private int matchdayNumber;
//..
//setters and getters defined
//..
//hashCode and equals methods overridden
}
public interface MyRepository extends JpaRepository<Matchday, Integer> {
#Query("... WHERE t.matchday.matchdayNumber < :matchday.matchdayNumber - 1;")
public findByCriteria(Matchday matchday);
}
The construction :matchday.matchdayNumber does not seem to be a valid syntax. Is there any other way to do it than passing the int value for matchdayNumber instead of a reference to Matchday object to this method?

Looks like this is possible with Spring JPA Data which allows SpEL in queries.
public interface MyRepository extends JpaRepository<Matchday, Integer> {
#Query("... WHERE t.matchday.matchdayNumber < :#{#matchday.matchdayNumber - 1}")
public findByCriteria(Matchday matchday);
}

Related

Spring Data Jpa Query methods are not invoking the repositoryBaseClass

I have a repository base class as defined below.
#NoRepositoryBean
public interface BaseRepository<T, ID extends Serializable> extends JpaRepository<T, ID> {
}
public class BaseRepositoryImpl<T, ID extends Serializable>
extends SimpleJpaRepository<T, ID> implements BaseRepository<T, ID> {
public BaseRepositoryImpl(JpaEntityInformation<T, ?> entityInfo, EntityManager entityMgr) {
super(entityInfo, entityMgr);
}
// ...
}
#Configuration
#EnableJpaRepositories(basePackages = "org.example",
repositoryBaseClass = BaseRepositoryImpl.class)
public class BaseConfig {
// additional JPA Configuration
}
I have defined a business repository class and a query method as seen below.
#Repository
public interface CarRepository extends BaseRepository<Car, Long> {
#Query("SELECT c FROM Car c Where active = 1")
List<Car> findAllActiveCars();
}
I have a test class which invokes the findAllActiveCars(). I am getting the expected results. But, that query method is not invoking any of the methods in BaseRepository class. How to customize the return values of the query methods?
You didn't show the methods that you did implement, so it is not clear why they don't get called, but since you want to decrypt entity fields, consider listening to JPAs entity lifecycle events. #PostLoad should be able to do the trick.
https://docs.jboss.org/hibernate/core/4.0/hem/en-US/html/listeners.html

MapStruct equivalent of hint(Dozer)?

In Dozer we are able to mention interfaces in hint during field mapping. How can we achieve the same in MapStruct ?
I could not put the exact code here. But, it is the similar as below.
We have here an Domain class example:
Class A<T extends B> extends C<T>
{
...
};
Where,
B is a abstract class.
C is a class which contains a List item which we have to map.
Similar is the structure of the classes and interfaces on DTO side.
So, the mapping is as below in Dozer:
<mapping>
<class-a>Domain.A</class-a>
<class-b>DTO.A</class-b>
<field>
<a>item</a>
<b>item</b>
<a-hint>Domain.B</a-hint>
<b-hint>DTO.B</b-hint>
</field>
</mapping>
In MapStruct how do we refer the interfaces as given in the hint in Dozer ?
Scenario:
We have:
public class ShopList<T extends Inp> extends Shop<T>\
{ ... };
where,
Inp is a abstract class with no fields in it like:
public abstract class Inp() { };
Shop is a class like:
public class Shop<T extends ShopInp> implements Serializbale
{ private List<T> items = new ArrayList<T>();
//getters and setters for the items };
ShopInp is a public interface with no fields in it like:
public interface ShopInp {} .
We have similar structure of classes on DTO side and Domain side.
Could you please let me know how would the mapper look like for the above scenario ?
In general, If we try mapping the ShopList class, then, how do we ensure that the T extends ShopInp and T extends Inp are also being mapped as a part of ShopList?
So called hints can be used via BeanMapping#resultType. MapStruct can use that to create the instance of the object you are trying to map. However, it will only create mapping for the elements of the abstract class, as it has no other information during compilation time (Dozer uses reflection and can detect the fields of the type during runtime).
Imagine you have this structure
public interface Fruit {
String getName();
String setName(String name);
}
public Apple implements Fruit {
...
}
public Banana implements Fruit {
...
}
public abstract class FruitDto {
private String name;
//getters and setters
}
public AppleDto extends FruitDto {
...
}
public BananaDto extends FruitDto {
...
}
public class Basket {
private Collection<Fruit> fruits;
}
public class BasketDto {
private Collection<FruitDto> fruits;
}
Your mapper can then look like:
#Mapper
public interface BasketMapper {
BasketDto map(Basket basket);
#BeanMapping(resultType = BananaDto.class)
FruitDto map(Fruit fruit);
}
Using this mapper all fruits in the BasketDto would be of an instance BananaDto (due to the BeanMapping#resultType and mapping would only be created for the elements of the FruitDto

How is entities inheritance implemented in Spring data mongodb

I've two entities Person, Employee and Employee1. I want to implement entities inheritance in Spring Data MongoDB. Like in Spring Data JPA, what are the equivalent annotations for #Inheritance and #PrimaryKeyJoinColumn in Spring Data MongoDB. Right now, I've implemented something like this:
interface Person {
String getId();
void setId(String id);
String getName();
void getName(String name);
}
#Document(collection = "person")
class PersonImpl implements Person {
#Id
String id;
// Getters and setters
// Constructors, equals, hashcode and toString methods
}
interface Employee extends Person {
int getNumberOfDependents();
void getNumberOfDependents(int numberOfDependents);
}
#Document(collection = "employee")
class EmployeeImpl extends PersonImpl implements Employee {
// Getters and setters
// Constructors, equals, hashcode and toString methods
}
interface Employee1 extends Person {
int getNumberOfDependents();
void getNumberOfDependents(int numberOfDependents);
}
#Document(collection = "employee1")
class Employee1Impl extends PersonImpl implements Employee1 {
// Getters and setters
// Constructors, equals, hashcode and toString methods
}
Repository structure:
public interface PersonRepository extends MongoRepository<Person, String> {
}
public interface EmployeeRepository extends MongoRepository<Employee, String> {
}
public interface Employee1Repository extends MongoRepository<Employee1, String> {
}
I'm saving the Person object first and then taking the ID of it and creating an Employee object with the same ID and saving it. This creates new object and hence I'm losing all the Person object stuff.
I also feel that I've to get the NoRepositoryBean implemented also.
I'm confused. Please help.
Here is one approach:
#Document(collection = "person")
class Person {
#Id
String id;
// Getters and setters
// Constructors, equals, hashcode and toString methods
}
Note that the collection field refers to "person" and not to "employee"
#Document(collection = "person")
class Employee extends Person {
String jobTitle;
// Getters and setters
// Constructors, equals, hashcode and toString methods
}
In this method you do not need to create a repository for each derived class
#Repository
public interface PersonRepository extends MongoRepository<Person, String> {}
Code example:
#Autowired
private PersonRepository personRepo;
public void test() {
Employee employee = new Employee("1", "teacher")
personRepo.save(employee)
Optional<Person> optionalPerson = personRepo.findById("1");
Employee employeeFromDb;
if (optionalPerson.isPresent()) {
employeeFromDb = (Employee)optionalPerson.get()
}
else {
// could not find in db
}
}
if you want to find all employees you should have a methode on MongoRepository
called
List<Employee> findAll();

Spring Data MongoDB No property get found for type at org.springframework.data.mapping.PropertyPath

I am using Spring Data MongodB 1.4.2.Release version. For Spring Data MongoDB, I have created the custom repository interface and implementation in one location and create custom query function getUsersName(Users users).
However I am still getting below exception:
Caused by: org.springframework.data.mapping.PropertyReferenceException:
No property get found for type Users! at org.springframework.data.mapping.PropertyPath. (PropertyPath.java:75) at
org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:327) at
org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:359) at
org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:359) at
org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:307) at
org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:270) at
org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:241) at
org.springframework.data.repository.query.parser.Part.(Part.java:76) at
org.springframework.data.repository.query.parser.PartTree$OrPart.(PartTree.java:201) at
org.springframework.data.repository.query.parser.PartTree$Predicate.buildTree(PartTree.java:291) at
org.springframework.data.repository.query.parser.PartTree$Predicate.(PartTree.java:271) at
org.springframework.data.repository.query.parser.PartTree.(PartTree.java:80) at
org.springframework.data.mongodb.repository.query.PartTreeMongoQuery.(PartTreeMongoQuery.java:47)
Below is my Spring Data MongoDB structure:
/* Users Domain Object */
#Document(collection = "users")
public class Users {
#Id
private ObjectId id;
#Field ("last_name")
private String last_name;
#Field ("first_name")
private String first_name;
public String getLast_name() {
return last_name;
}
public void setLast_name(String last_name) {
this.last_name = last_name;
}
public String getFirst_name() {
return first_name;
}
public void setFirst_name(String first_name) {
this.first_name = first_name;
}
}
/* UsersRepository.java main interface */
#Repository
public interface UsersRepository extends MongoRepository<Users,String>, UsersRepositoryCustom {
List findUsersById(String id);
}
/* UsersRepositoryCustom.java custom interface */
#Repository
public interface UsersRepositoryCustom {
List<Users> getUsersName(Users users);
}
/* UsersRepositoryImpl.java custom interface implementation */
#Component
public class UsersRepositoryImpl implements UsersRepositoryCustom {
#Autowired
MongoOperations mongoOperations;
#Override
public List<Users> getUsersName(Users users) {
return mongoOperations.find(
Query.query(Criteria.where("first_name").is(users.getFirst_name()).and("last_name").is(users.getLast_name())), Users.class);
}
/* Mongo Test function inside Spring JUnit Test class calling custom function with main UsersRepository interface */
#Autowired
private UsersRepository usersRepository;
#Test
public void getUsersName() {
Users users = new Users();
users.setFirst_name("James");`enter code here`
users.setLast_name("Oliver");
List<Users> usersDetails = usersRepository.getUsersName(users);
System.out.println("users List" + usersDetails.size());
Assert.assertTrue(usersDetails.size() > 0);
}
The query method declaration in your repository interface is invalid. As clearly stated in the reference documentation, query methods need to start with get…By, read_By, find…By or query…by.
With custom repositories, there shouldn't be a need for method naming conventions as Oliver stated. I have mine working with a method named updateMessageCount
Having said that, I can't see the problem with the code provided here.
I resolved this issue with the help of this post here, where I wasn't naming my Impl class correctly :
No property found for type error when try to create custom repository with Spring Data JPA

How to read the new XStreamConverter parameters?

Since version 1.4.2 of XStream, the XStreamConverter annotation takes additional parameters (very good feature and just what I need).
#XStreamConverter(value=CustomXStreamConverter.class, strings={xyz"})
private List<String> phones;
But how can I read this values (xyz) in my custom converter?
public class CustomXStreamConverter implements Converter {
//?
}
I figure out the solution, just override the class constructor in order to receive the parameter.
public class CustomXStreamConverter implements Converter {
private String alias;
public ListToStringXStreamConverter(String alias) {
super();
this.alias = alias; //xyz
}
//...